Radiodetector



March 16 1926. 1,576,783

J. B. PITTs RADIODETECTOR Filed Jan. 31, 1925 Patented Mar. 16, i926.

TOI-IN B. PTTS, 0F WINNETKA, ILLINIS.

RADIODEIECTOR.

Application filed January 31, 1925. Serial No. '5,983.

To ZZ fui/2,0m t may concern:

Be it known that I, JOHN B. Pi'r'r's, a citizen of the United States of America, residing at lllinnetka. in the ycounty of Cook and State of Illinois, have invented certain new and useful Improvements in Radiodetectors, of which the following a speciiication.

This invention relates to the solid element type of detectors or adapters employed in radio-telephony apparatus, and has for its various objects To provide a structural formation and combination of parts in a shell shaped holder for the complementary electrical elements of the detector, by means of which said elements are substantially supported in an adj ustable manner in proper operative relation to cach other, and are enclosed' and protected from dust and other injurious local influence. The holder is adapted for ready and convenient attachment to the front, rear or base of the enclosing cabinet of the apparatus.

To provide av structural formation of parts, whereby an electrical clement of a crystal or like solid detector element ispheld in a fixed and effective condition in the holder, with an avoidance of asolder or like metallic embedment for holding a crystal or like element in conductive position, andthe consequent decrease in the sensitivity of the element, all as will hereinafter more fully appear. In the accompanying drawing:

Fig'. l, is a side elevation. l

Fig. 2, is a central longitudinal section, showing the invention as applied to the cats whisker type of crystal detectors.

Fig. 3, is a perspective view of the detector parts shown' in Fig. 2, in separated condition.

Fig'. 4E, is a similar perspective view of the parts if the adjustable unit of a crystal detcctor is of the type in which one crystal has conductive contact with another crystal.

Fig. 5, is a longitudinal section of the detector of the type referred to in connection with Fig.

Like reference numerals indicate like parts in the several views.

The main casing l of the detector is preferably formed of a section of metallic tubing, t-hreaded internally along its length for screw-threaded engagement with other asso-l ciated parts of the device.

The shell or container for the stationar i crystal or like solid electrical element of the wellknown ccats whisker detector, is formed of a suitable nonelectric material, and consists of an'externally and internally screw threaded tubular member 2, provided ato-ne 0nd with an out turned stop collar or flange 8, and at the other end with an oriliced head formed by an inturned tlange 4; as shown. The central orifice so formed aifords a bearing or abutment for a crystal'elcn'ient 5 which is exposed through said oritice for electrical contact 'with the complementary crystal or other usual ele ment of the detector. Y

In the construction shown, the external screw threads of the shell or container 2 have positioning engagement with the screw threads in an end ofthe main casing l, with the stop collar 3 providing a stop or abutmentfor the parts, as well as a` part of the attaching means for a terminal ring member G, a side extension of which carries a screw terminal 7 for connection of a line wireof the apparatus.

Associated with the shell or container 2 is an externally screw threaded follower head 8 of metal, adapted to screw into theinternaliy screw threaded bore of the'shell or containerk 2 to firmly clamp and'position the crystal elemento in place in the cavity of said shell asshown. At `one end the head 8 is provided with a fixed operating stem 9 for convenient rotation in an adjustment of parts, and in the preferred 'construction shown the stem 9 is screw threaded along its length yfor the` reception lof binding nuts l0, by which attachment is made to supporting plate'bra'cket ll, preferably of the Z form shown, and by means of which the detector is supported in the enclosing casing 'of a radio apparatus. .ln the construction 'shown the bracket plate 1l is interposed between the flanged end 3 of the shell 2 and the aforesaidnuts 10, fwith `said nuts also acting to hold between them a conducting line wire of the circuit of the apparatus. l

The other and complementary electrical element l2 of the detector has, as usual, an adjustable relation to the aforesaid fixed crystal like element 5, and may be of the type, comprising' a spiral or serpentine section 13 of wire, the free end of which is y*adapted for electrical contact with the crystal element 5. while its other end has fixed attachment to a stud 14 on one end of an externally screw threaded head 14 having adjustable engagement with the internal screw threads of the l Ul) main casing 1. The attachment being preferably attained a bent end 13 et' thefwire spiral'lB litting a diainetric slit in the "afore- .said stud 14;. ln this Sneciic arrangement of parts as shown in Figs. 2 and"3, the head 14: is of a solid form and is with a central fixed stem 15 havingY anv operating handle 16 for convenient rotation oi the head in eil'ecting an initial adjnstment or replacement of parts.

In Figs. et and 5, a modiiied arrangement is shown inn'hich a crystal element 17 constitntes the adjustable electrical contact element of the detect-or, with a/modilied forma tion et the adjustable follower head orfsaid crystal as follows,

The headv 1S above referred to, is externally screw threaded,was'y in vthe case of the Shell or container 2 heretofore described,

and is formed with avsci'ewthreaded borel at one end of which is an oriliced head formed by an inturned annular flange w19',

similar to said` Sheller container 2, With the central orilice so formed'proyiding a bearing or abutment -for the crystal element 17, which projects through said orifice, forf electrical Contact with 'the stationary crystal element aforesaid. In this,v modified construction an externally screw threaded plug 20 has adjuetable engagement nf'ith the screw threaded bore of the head 18 to trmly clamp and hold the crystal element 17 in proper position.

Atone end the plug 2O carries a .stem 21 having an operating handle or knob y22 at its outer end for the convenient rotation of said plug and the head 18 in eecting a replacement or an adjustment Qparts.

Having' thus fully describedmy invention what I claim and desire to secure by Lettere Patent, :f V

1. ln a radio detector, the combination of Aa main casing of conducting material formed with a serev threaded bore itel length, al eontainerol' non-conducting material screnV threaded externally for. engagement in one end ot' the main casing and formed with a screw threaded'cavity tot' the reception of a crystal Contact member and. with a centrally 'orificed end wall providing a bearing for said crystal member,

an enternally screw threaded follower head of conducting material having engagement in the bore' of the container to hold said crystal member in position, an externally screw threaded plug of conducting material carrying an electrical Contact member in operative relation to the crystal member and formedr with a screw threaded periphery in adjustable engagement with the bore of the main casing, a terminal member connected to the main easing,`and a companion ter minal member vconnected to the aforesaid follower head of the container.

' radioV detectorQthe combination oi a n' Liircvasing of conducting material 'formed nfitha ser n' threaded bore along its length, container' of non-conducting material screw threaded externally for engagement in o1 end et the main casing and formed with a screw threaded cavity tor the reception ot' a crystal Contact member and with a. centrally orifice-,d end Wall providing a bearing for said crystal member and with an, endy turned flange at its other end, an externally screw threaded follower head of conductilig material having engagement in the bore et the container to hold said crystal meniber in position, an externally screw threaded plug of conducting material carryan lelectrical contact member in opera tive relation to the crystal member, and formed with a screw threaded periphery in adjustable engagement With the bore of the main casing and with a central screw threaded stem extending beyond the main casing, an externallj,' screw threaded plug ot condncting material carrying an electrical cent-act member in operative relation tofthe crystal member and Jformed with a screw threaded periphery in adjustable engagement with the bore of the main casing7 a terminal member ot' the ring 'form arranged'between an end et the main casing and the end `Bange of the aforesaid container, and a compa-nien tern'iinal member cennected'to the central stem or the il'ollen'er 11C/21d aforesaid;

Signed at Chicago, lllinfjis, this 28th day of January, 1925. 

